Air-brake mechanism



July 10, 1923.

' .129 FIG. ,2

L. G. BLACK AIR BRAKE MECHANISM Filed March 30 INVENTOR. L6. 51.. HCA

ATTORNEY Patented July 10, 1923. f; 3 i

UNITED STATES PATENT oFFicE.

I. LESLIE G. BLACK, OF SIOUX CITY, IOWA.

" AIR-BRAKE MECHANISM.

Application filed March 30, 1921. Serial No. 457,022.

To all whom it may concern: the retaining valves which is comparatively Be it known that I, LESLIE Gr. BLACK, a simple and inexpensive in construction, yet citizen of the United States, and a resident thoroughly dependable and eflicient in opof Sioux City, in the county of Woodbury eration. and State of Iowa, have invented certain These and other objects and advantages new and useful Improvements in Air-Brake are successfully attained in the embodiment Mechanism, of which the following is a hereinafter described, defined in the apspecification. pended claims and illustrated in the accom- The railway airbrake systems in common panying drawings, which form a part of use employ so-called retaining valves, this application, and in which like charmounted on every coach and car and so asacters of reference indicate corresponding sociated with the triple valves as to retain parts throughout the several views, of a light breaking pressure, when the retaining which, valves are closed. Fig. 1 is an enlarged vertical section of This system sufi'ers from the fact that the the device of my invention and the assoretaining valves must be individually manuciated triple valve, the parts being shown in ally controlled, which necessitates a trainnormal position and the triple valve being man going over or through the train to cut away; and turn them up or turn them down, the Fig. 2 is a similar view of my device and terms commonly employed by trainmen for the triple valve, the parts being shown in 7 accordingly closing and opening the retain operative position. ing valves. While I have illustrated and hereinafter A further evil of the system resides in the described but one embodiment of the invenfact that when the valves are closed the tion, I would not be understood as being brakes'are energized until the valves are limited to such specific construction, for opened. For example, when the retaining various alterations and modifications may valves have been turned up prior to debe made in the details of construction and scending a gradient, they are left in this arrangement of parts herein disclosed withposition during the entire descent and the out departing from the spirit and scope of brakes remain energized until trainmen the invention, as defined in the appended again open the retaining valves, which reclaims. quires considerable time, if the train is long. Referring now to the illustrations, I have At the foot of the gradient the train must shown the usual quick-action triple-valve be brought to a stop until the valves are embodyin the triple valve body, 4, having again opened, or the brake pressure opposes the cylindrical chamber, 5, closed by the the power of'the locomotive. cylinder cap, 6, and in which reciprocates My invention has, therefore, for its prithe triple piston, 7 controlling the slide mary object the production in an air-brake valve, 8, which normally places the exhaust system of means which obviate the abovepassage, 9, in communication with the pasrecited evils and objections, and places the sage, 10, leading to the brake cylinder to retaining valves under the control of the through the tube 11; and when a reductlon engineman. is made in the train line, exposes the pas- A further object of the invention is the sage, 10, to pressure fromthe auxiliary resproduction in an air-brake system of imervoir, 30. 12 is the usual check-valve case, proved means whereby the retaining valves having the induction passage 13, which it are automatically and simultaneously cOn- Will be understood is connected with the trolled-by the train-line pressure, train line, 14, whereby pressure from the Still another object of the invention is the latter enters the cylinder cap 6 forcing the production in an air-brake system of imtriple piston 7 inwardly sufiiclently to exproved means for the automatic control of pose the feed-groove 15, whereby pressure enters the auxiliary reservoir through the triple valve-body, 4.

The usual threeway retaining valve 18 represented by the casing, 16, having aweight-controlled valve, 17, normally closing an exhaust passage 18, registering with a passage 19 in the valve 20, rotated by means of the handle 21 to place the passage 18 in communication with the induction passage 22 of the retaining valve, or, when turned down at right angles, the retaining valve passage 18 is closed, and the valve passages, 19 and 23, register, respectively, with the induction passage 22 and the exhaust passage, 24.

' This retaining valve, as now used, communicates with the usual free air exhaust, 9, in the triple valve body.

The structure above described represents no part of my present invention, but serves to illustrate those elements of the air-brake system now in use with which the device of my invention is associated.

Between the triple valve exhaust and the retaining valve is interposed my novel automatic device, which consists, preferably, 0itwo cylinders, 26 and 27. disposed in paral-j lelism, cast en bloc and provided with a hanger, 28, adapted to be secured to the underf-raI-ne of a car, 29.

Within the cylinder, 26, is a piston, 31; having a stem, 32, carrying a slide valve, 33, within a valve chamber, 34, on the said cylinder. The slide valve, 33, normally closes a port, 35, leading from the cham ber, 34, to the opposite end of the cylinder, 27, within which reciprocates a piston, 38, having a stem, 39, carrying a slide valve, 40, positioned in a slide-valve chamber, 41, on the cylinder 27, and provided with a screened exhaust opening, 42, which is nor mally opened, and when a reduction is made in the train-line pressure the said exhaust opening is closed by the slide valve, 40, as will presently be made more clear.

Between the slide valve, 40, and the head of the valve chamber, 41, is a buffer spring 43. serving to prevent impact of the slide valve with the head of the valve chamber. The head of the valve chamber is provided with an induction opening, 44, and an eduction' opening, 45, the former being connected by a suitable duct, 46, with the triple exhaust opening, 25; and the latter is con? nectedby a suitable duct, 47, with the induction passage, 22, of the retaining valve.

Betweenthe piston, 31, and the head, 48, of the eylinder,f26, is interposed a compressing spring', 49, the piston, 31, being provided with a second steam, 50, engageable withthe stem, 63, of; a puppet valve, 52, adapted to co-act with a suitable valve seat, 53, in an opening, 51, in the cylinder head.

The valve, 52, is enclosed in a suitable valve chamber, 54, on the cylinder head, .48,

and closed by a suitable head including a plate, 55, and a central screw plug, 56, therein, between which plug and the valve, 52, is interposed a comparatively light compressionspring, 57, encircling a small stem, 58, on the valve, 52, by virtue of which construction the screw plug may be turned to vary the tension of the spring, 57.

The valve chamber, 54, communicates with the adjacent end of the cylinder, 27, through a suitable port, 59, and between the head, 48,, and the piston, 31, the cylinder, 26, is provided with a screened exhaust opening, 60.

The head of the slide valve chamber, 34, is provided with an induction opening, 61, connected by a. suitable duct, 62, with the auxiliary reservoir, 30. p

The combined tension of the springs, 49, and 57, when compressed, is substantially equal to the normal train line pressure, which, it will be understood, is usually 85 to 95 pounds, and, for example, we will assume that the tension ofth'e spring, 49. under compression is pounds and that of the spring, 57, is 15 pounds. The port, 35, and slide valve, 33, areso related that the normal train line pressure entering the slide valve chamber, 34, from the auxiliary reservoir acts on the piston, 31, to cause the valve, 33, to close the said port and hold the valve, 52, from its seat, permitting pressure within the cylinder, 27, to escape through port 59, the valve chamber 54, the cylinder head opening, 51, and the exhaust opening, 60, all, as clearly illustrated in Fig. 2.

When either a service reduction or an emergency reduction is made in the train line, the pressure within the valve chamber, 34, being thereby reduced, the spring, 49, forces the piston in the direction of the valve chamber, 34, causing the spring, 57, to seat the puppet valve, 52, and the slide valve. 33, to open the port, 35, whereby sufficient pressure within the slide valve chamber, 34, enters the cylinder, 27, through ort 35, to force the piston, 38, in the direction of the valve chamber, 41, thereby causing the slide valve, 40, to close the exhaust port, 42, all as presented in Fig. 3, in which view it will be seen that pressure escaping from the triple exhaust into the valve chamber, 41, can escape only through the retaining valve, which, it will be understood, is always closed or turned up and in connection with my device functions as usual and retains the pressure for which it is intended, while the slide valve 40, is in the position shown in Fig. 3. Then, when the engineman starts to recharge the train line, the pressure entering the valve chamber, 34, from the auxiliary reservoir acts on the piston, 31. to cause the valve, 33, to blank the port, 35, and as the train line receives its final 15 pounds of pressure the puppet valve, 52, is forced from its seat, permitting the pressure entering the valve chamber, 41, to force the piston to the position shown in Fig. 2 to open the exhaust port, 42, through which the braking pressure is then free to exhaust. e

By virtue of my construction it] will be now clear that they retaining valves are 'en tirely within the control of the enginemen nd they offer resistance to the braking pressure only when the train-line pressure sub-normal. H I v Having thus iescribed my invention, what I claim as new and desire to secure by Let ters Patent of the United States is 1. A brake system embodying a source of the retaining valve, including a valve chamber communicating with said communicating passage and having an exhaust opening, valve mechanism within said chamber, actuated from said source of pressure to close the exhaust opening when the pressure in said source is subnormal, and actuated by pressure from the communicating passage to open the exhaust opening when the pressure in said source is normal. v e

2. In a brake system embodying a source of fluid pressure, brake mechanism including a fluid-pressure passage, an exhaust passage, valve mechanism for placing said passages in and out of inter-communication, a fluidpressure retaining valve, a communicating passage between the exhaust passage and the retaining valve, and means for control ling the retaining valve, including a valve chan'iber communicating with said communicating passage, and having an exhaust open ing, a second valve chamber communicating with said source of pressure, a port between said chambers a .valve in said second chamber governed by normal pressure from said source to close said port, a valve in said first chamber actuated by pressure from the communicating passage to open the exhaust opening when the pressure in said source is normal, and yieldable means for forcing the valve in said second chamber to open said port when pressure in said source is subnormal, whereupon pressure entering said first chamber through said port causes the valve in said first chamber to close the exhaust opening.

3. In a brake system, the combination with a source of fluid pressure, brake mechanism including a fluid-pressure-passage, an ex haust passage, and means for placing said passages in and out of intercommunication,

of a fluid-pressure-retaining valve, a communicating passage between the retaining valve and the exhaust passage and having a normally open exhaust opening, and valve mechanism governed by the source of fluid pressure to close the exhaust opening when a the pressure in said source is subnormal, and

actuated by pressure from saidcommunicating passage to open the exhaust openin when the pressure in said source is norma 1-. In a brake system,the combination with a-source of fluid pressure, brake mechanism including a fluid-pressure-passage, an exhaust passage, and means for placing said passages in and out of intercommunication, of a fiuid-pressure-retaining valve, a communicating passage between the retaining valve and the exhaust passage, a valve chamber communicating with the said communieating passageand having a normally open exhaust opening, and slide valve mechanism within the chamber governed by the source of fiuidpressure to close the exhaust openin when the pressure in said source is subnormah 5. In a brake system, the combination with a source of fluid pressure, brake mechanism including a fiuid-pressure-passage, an exhaust passage, and means for placing said passages in and out of intercommunication, ofa fluid-pressure retaining valve, a communicating passage between the retaining valve and the exhaust passage, a valve chamber communicating with the said communicating passage and having a normally open exhaust opening, and valve mechanism within the chamber governed by the source'of fluid-pressure to close the exhaust openingwhen the pressure in said source issubnormal and governed by pressure from the said communicating passage to close the exhaust opening when pressure in said source is normal.

6Q In a brake system, the combination with a source of fluid pressure, brake mechanism including a fluid-pressure-passage, an exhaust passage, and means for placing said passages in and out of intercommunication, of a fluid-pressure-retaining valve, a communicating passage between the retaining valve and the exhaust passage, a valve chamber communicating with the said communieating passage and having an exhaust opening, a second valve chamber communicating with said source of pressure, a'portbetween said chambers, a valve in said second chamber governed by normal pressure from said source to close said port, a valve in said first chamber actuated by pressure from the communicating passage to open the exhaust opening when the pressure in said source is normal, and yieldable means for forcing the valve in the second chamber to open said port when pressure in said source is subnormal; whereupon pressure entering said Pill sure,

first chamber through said port causes the valve in said first chamber to close the exhaust opening.

7. A retaining valve controlling means for a brake system having a source of fluid pressure, a brake-pressure exhaust and a fluid pressure-retaining yalve communicating with the exhaust, comprising a chamber adapted to communicate with the exhaust and having an exhaust passage, and fluidfrom the brake-pressure exhaust to open the exhaust passage when the said source of pressure is normal. 8. A retaining valve controlling means for a brake system having a source of presa brake pressure exhaust and a pressure-retaining valve communi eating with the exhaust, comprising a chamber adapted to communicate with the exhaust and having an exhaust passage, a valve within said chamber actuated by pressure from the brake-pressure exhaust to open the exhaust passage, a second chamber adapted to receive pressure from said source, a passage between said charm: hers, a valve within the second chamber ac tuatecl by. normal pressure from the source to hold the latter passage closed, and means for opening the latter passage when the Source of pressure is subnor nal, whereby pressure enters said first chamber through the latter passage, said first chamber valve being adaptedto, be forced to close the exau Pass by pre s re t g sa d fi t chamber irom said second chamber.

9. A retaining valve controlling meansfor brake system having a source of fluid pressure, a brake pressure exhaust and a fluidpressure-retaining valve communicating with the exhaust, comprising a cylinder, having a valve chamber adapted to com- Inunicate withthe brake pressure exhaust and having an exhaust passage, a pis: ton within the cylinder, a valve within the chamber for the control of the exhaust passage governed by the pis ton, whereby pressure from the exhaust pases; acts n e "p t toferce h v l e open, chamber adapted to communicate with said source of pressure, a passage bewas ai lla t cham e and s d first ylinder, whereby pressure enters thereinto act on the piston to force said first chamber valvelclosed, and means controlled by the source of pressure for normally closing the latterpassage, and causing it to open when pressure at the source is subnormal.

10. A retaining valve controlling means brake system having a source of fluid pressure, a brake pressure exhaust and a fluid-P e su etain es va m uniw WWW? mg with the exhaust, comprising a cylinder, having a valve chamber adapted to communicate with the brake-pressure exhaust and having an exhaust passage, a piston within the cylinder, a valve within the chamber for the control of the exhaust passage governed by the piston, whereby pressure from the exhaust passage acts on the piston to force the valve open, a cl amberaclapted to communicate with said source of pressure, a passage between said latter chamber and said first cylinder, whereby pressure enters therein to act on the piston'to force said first chamber valve closed, means controlled by the source of pressure for normally closing the latter passage and causing it to open when pressure at the source is subnormal, and a normallyopen valved exhaust passage from said cylinder controlled by said means;

11. A retaining valve controlling means for a brake system having a source of fluid pressure, a brake pressure exhaust and a fluid-pressure-retai ning valve communicating with the exhaust, comprising a cylinder, having a valve chamber adapted to communicate with the brake-pressure-exhaust and having an exhaust passage, a piston within the cylinder, a valve within the chamber for the control of the exhaust passage governed by the piston, whereby pressure from the exhaust passage acts on the piston to force the valve open, a second cylinder having a valve chamber adapted to receive pressure from said source, a passage between the latter chamber and the first cylinder, through which pressure acts on the piston to close said first chamber valve, a piston within the second cylinder, a valve in the second chamber controlled by the second piston to govern the latter passage, said second piston and valve being so constructecland mounted that normal pressure acts on the latter piston to close the latter passage, and yieldable means causing the latter valve to open said latter passage when pressure entering the second chamber is subnormal.

12. A retaining valve controlling means for a brake system having a source of fluid pressure, a brake pressure exhaust and a fluid-pressure-retaining valve communicating with the exhaust, comprising a cylinder, having a. valve chamber adapted to communicate with the brake-pressureexhaust and having an exhaust passage. a piston within the cylinder, a valve within the chamber for the control of the exhaust passage governed by the piston, whereby pressure from the exhaust passage acts by the piston to force the valve open, a second cylinder having a valve chamber adapted to receive pressure from said source, a passage between the latter chamber and the first cylinder, through which pressure acts on the piston to close said first chamber valve, a piston within the second cylinder, a valve in thesecond chamber controlled by the second piston to govern the latter passage, said second piston and valve being so constructed and mounted that normal pressure acts on the latter piston to 5 close the latter passage, yieldable means causing the latter valve to open said latter passage when pressure entering the second chamber is subnormal, and a normally-open valved exhaust passage from the first cylinder controlled by said second piston.

In testimony whereof, I have hereunto set my hand this 25th day of March, 1921.

LESLIE G. BLACK. 

